Pixel arrangement structure for organic light emitting diode display

ABSTRACT

A pixel arrangement structure of an organic light emitting diode (OLED) display is provided. The pixel arrangement structure includes: a first pixel having a center coinciding with a center of a virtual square; a second pixel separated from the first pixel and having a center at a first vertex of the virtual square; and a third pixel separated from the first pixel and the second pixel, and having a center at a second vertex neighboring the first vertex of the virtual square. The first pixel, the second pixel, and the third pixel have polygonal shapes.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/005,753, filed Aug. 28, 2020, which is a continuation of U.S. patentapplication Ser. No. 13/872,018, filed Apr. 26, 2013, now U.S. Pat. No.10,832,616, which claims priority to and the benefit of Korean PatentApplication No. 10-2013-0044993, filed in the Korean IntellectualProperty Office on Apr. 23, 2013, and is a continuation in part of U.S.patent application Ser. No. 13/614,197, filed Sep. 13, 2012, now U.S.Pat. No. 9,818,803, which claims priority to and the benefit of KoreanPatent Application No. 10-2012-0022967, filed in the Korean IntellectualProperty Office on Mar. 6, 2012. The entire contents of all of the aboveapplications are incorporated herein by reference.

BACKGROUND 1. Field

Aspects of embodiments of the present invention relate generally to apixel arrangement structure for an organic light emitting diode (OLED)display.

2. Description of the Related Art

A display device is a device that displays an image. Recently, an OLEDdisplay has been drawing attention.

The OLED display has a self-luminous characteristic. Because the OLEDdisplay does not need a separate light source, unlike a liquid crystaldisplay, it can have a relatively smaller thickness and weight thanliquid crystal displays. In addition, the OLED display exhibitshigh-quality characteristics such as low power consumption, highluminance, high response speed, etc.

In general, the OLED display includes a plurality of pixels for emittinglight of different colors. The plurality of pixels emit light to displayan image.

Here, the pixel refers to a minimum unit for displaying the images. Forinstance, there may be a gate line, a data line, and a power line suchas a driving power line to drive each pixel. In addition, there may bean insulation layer such as a pixel definition layer to define an areaand a shape of each pixel. Further, each pixel may be positioned betweenits neighboring pixels.

An organic emission layer included in the pixel of an OLED display maybe deposited and formed by using a mask such as a fine metal mask (FMM).When reducing a gap between the neighboring pixels to obtain a highaperture ratio of the pixels, deposition reliability may bedeteriorated. On the other hand, when increasing the gap between thepixels to improve the deposition reliability, the aperture ratio of thepixels may be deteriorated.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the invention andtherefore it may contain information that does not form the prior artthat is already known in this country to a person of ordinary skill inthe art.

SUMMARY

Aspects of embodiments of the present invention relate generally to apixel arrangement structure for an OLED display. More particularly,aspects of embodiments of the present invention relate to a pixelarrangement structure of an OLED display that displays an image byemitting light through a plurality of pixels.

An exemplary embodiment of the present invention provides a pixelarrangement structure for an OLED display having an improved apertureratio of each of the pixels while efficiently setting up gaps betweenthe pixels.

According to an exemplary embodiment of the present invention, a pixelarrangement structure of an organic light emitting diode display isprovided. The pixel arrangement structure includes: a first pixel havinga center coinciding with a center of a virtual square; a second pixelseparated from the first pixel and having a center at a first vertex ofthe virtual square; and a third pixel separated from the first pixel andthe second pixel, and having a center at a second vertex neighboring thefirst vertex of the virtual square.

The second pixel may include a pair of second pixels. The second pixelsmay be separated from each other by the first pixel.

The third pixel may include a pair of third pixels. The third pixels maybe separated from each other by the first pixel.

The second pixels and the third pixels may enclose the first pixel inthe virtual square.

The first pixel, the second pixels, and the third pixels may havepolygonal shapes. The second pixels and the third pixels may have alarger area than the first pixel.

The first pixel may have a quadrilateral shape. The second pixels andthe third pixels may have hexagonal or octagonal shapes.

The second pixels and the third pixels may have octagonal shapes.

The second pixels and the third pixels may have a same area. A distancebetween the first pixel and the second pixels, a distance between thefirst pixel and the third pixels, and a distance between the secondpixels and the third pixels may be a same first length.

The first pixel may include a plurality of first pixels. The pluralityof first pixels may have a same quadrilateral shape. A distance betweenneighboring ones of the plurality of first pixels may be a second lengththat is longer than the first length.

The second pixels may have a larger area than the third pixels. Adistance between the second pixels and the third pixels may be a firstlength. A distance between the first pixel and the second pixels, and adistance between the first pixel and the third pixels may be a samesecond length.

The first pixel may include a plurality of first pixels. The pluralityof first pixels may have a same quadrilateral shape. A distance betweenneighboring ones of the plurality of first pixels may be a third lengththat is longer than the first length and the second length.

The first pixel may include a plurality of first pixels. Neighboringones of the plurality of first pixels may have quadrilateral shapes thatare symmetrical to each other. A distance between the neighboring onesof the plurality of first pixels may be a third length that is longerthan the first length and the second length.

The first pixel may include a plurality of first pixels. Neighboringones of the plurality of first pixels may have quadrilateral shapes thatare symmetrical to each other.

The second pixels may have a larger area than the third pixels.

The third pixels may have a larger area than the second pixels.

The first pixel, the second pixel, and the third pixel may be configuredto emit different color lights.

The first pixel, the second pixel, and the third pixel may be configuredto emit green light, blue light, and red light, respectively.

According to an exemplary embodiment of the present invention, a pixelarrangement structure of an organic light emitting diode (OLED) displayis provided. The pixel arrangement structure includes: a first pixelhaving a center coinciding with a center of a virtual square; a secondpixel separated from the first pixel and having a center at a firstvertex of the virtual square; and a third pixel separated from the firstpixel and the second pixel, and having a center at a second vertexneighboring the first vertex of the virtual square. The first pixel, thesecond pixel, and the third pixel have polygonal shapes.

In one embodiment, the second pixel includes a pair of second pixels,and the second pixels are separated from each other by the first pixel.

In one embodiment, the third pixel includes a pair of third pixels, andthe third pixels are separated from each other by the first pixel.

In one embodiment, the second pixel includes a pair of second pixels,the third pixel includes a pair of third pixels, and the second pixelsand the third pixels enclose the first pixel in the virtual square.

In one embodiment, each of the second pixels and the third pixels islarger in area than the first pixel.

In one embodiment, the first pixel has an octagonal shape, and at leastone of the second pixel or the third pixel has an octagonal shape.

In one embodiment, the first pixel has an octagonal shape, and one ofthe second pixel or the third pixel has a hexagonal shape and an otherof the second pixel or the third pixel has a quadrilateral shape.

In one embodiment, the virtual square includes a pair of virtual squaressharing a common side, the first pixel includes a pair of first pixelshaving centers respectively coinciding with centers of the virtualsquares, and the first pixels have octagonal shapes that are symmetricalto each other.

In one embodiment, each of the second pixels is larger in area than eachof the third pixels.

In one embodiment, a distance between the first pixel and the secondpixels as well as a distance between the first pixel and the thirdpixels is a same first length.

In one embodiment, the virtual square includes a pair of virtual squaressharing a common side, the first pixel includes a pair of first pixelshaving centers respectively coinciding with centers of the virtualsquares, a distance between each of the second pixels and the thirdpixels is a same second length, and a distance between the first pixelsis a third length that is longer than the first length and the secondlength.

In one embodiment, the first pixel, the second pixel, and the thirdpixel are configured to emit different color light.

In one embodiment, the first pixel is configured to emit green light,one of the second pixel or the third pixel is configured to emit bluelight, and an other of the second pixel or the third pixel is configuredto emit red light.

According to an exemplary embodiment of the present invention, the pixelarrangement structure of the OLED display improves the aperture ratio ofthe pixels while efficiently setting up the gaps between the pixels.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of a pixel arrangement structure of an OLED displayaccording to a first exemplary embodiment.

FIG. 2 is a view of a pixel arrangement structure of an OLED displayaccording to a second exemplary embodiment.

FIG. 3 is a view of a pixel arrangement structure of an OLED displayaccording to a third exemplary embodiment.

FIG. 4 is a view of a pixel arrangement structure of an OLED displayaccording to a fourth exemplary embodiment.

FIG. 5 is a view of a pixel arrangement structure of an OLED displayaccording to a fifth exemplary embodiment.

FIG. 6 is a view of a pixel arrangement structure of an OLED displayaccording to a sixth exemplary embodiment.

DETAILED DESCRIPTION

Several exemplary embodiments according to the present invention aredescribed hereinafter in detail with reference to the accompanyingdrawing to allow one of ordinary skill in the art to practice theinvention without undue experimentation. The present invention can beembodied in several different forms, and is not limited to the exemplaryembodiments that are described herein.

In order to clarify the description of embodiments of the presentinvention, parts that are not related to the invention may be omitted.In addition, the same elements or equivalents are referred to with thesame reference numerals throughout the specification.

Further, since sizes and thicknesses of constituent members shown in theaccompanying drawing may be arbitrarily given for better understandingand ease of description, the present invention is not limited to theillustrated sizes and thicknesses.

In addition, unless explicitly described to the contrary, the word“comprise” and variations such as “comprises” or “comprising” will beunderstood to imply the inclusion of stated elements but not theexclusion of any other elements.

Nevertheless, even though each of the pixels are drawn as stereotypicalpolygonal shapes in the drawings, the present invention is not limitedto this shape. That is, the shapes of the pixels may be modified toavoid interference with the other components of the OLED (e.g., wirings)within the spirit and scope of the appended claims.

A pixel arrangement structure (or pixel arrangement) of an OLED displayaccording to a first exemplary embodiment will be described withreference to FIG. 1. FIG. 1 is a view schematically showing a portion ofpixels forming an OLED display.

As shown in FIG. 1, the pixel arrangement structure of the OLED displayincludes a plurality of first pixels 100, a plurality of second pixels200, and a plurality of third pixels 300. Here, the pixel refers to aminimum unit for displaying an image (for example, the minimumaddressable unit of the display).

Further, among the first pixels 100, the second pixels 200, and thethird pixels 300, power lines for driving each of the pixels, such as agate line, a data line, a driving power line, and the like, may belocated. In addition, an insulation layer, such as a pixel defininglayer, for defining each of the pixels may be disposed. Finally, an OLEDincluding an anode, an organic emission layer, and a cathode tocorrespond to each of the first pixels 100, the second pixels 200, andthe third pixels 300 may be disposed. These configurations aretechnologies known in the art and further description thereof is omittedfor ease of description. A shape of each of the pixels may be defined bythe power lines, the pixel defining layer, the anode, or the like, butis not limited thereto.

In the pixel arrangement of FIG. 1, each of the first pixels 100 has asmaller area than neighboring second pixels 200 and third pixels 300,and has a quadrilateral (i.e., four-sided) shape among polygon shapes.For example, in the pixel arrangement of FIG. 1, each of the firstpixels 100 has the same quadrilateral shape (e.g., a square or rhombus).The first pixels 100 are spaced apart from each other and arranged inrows, such as along a first virtual straight line VL1. The first pixels100 emit green light, and may include an organic emission layer foremitting green light.

The second pixels 200 are arranged diagonally with respect to the firstpixels 100, such as at first vertices P1 along one diagonal of a virtualsquare VS having one of the first pixels 100 as a center point (orcenter) of the virtual square VS. In a similar fashion, the third pixels300 are arranged diagonally with respect to the first pixels 100, suchas at second vertices P2 along the other diagonal of the virtual squareVS.

In the virtual square VS, each of the second pixels 200 is separatedfrom the first pixel 100, and is centered at one of the first verticesP1 of the virtual square VS. Each of the second pixels 200 has a largerarea than the neighboring first pixel 100 and has an octagonal (i.e.,eight-sided) shape. In FIG. 1, the second pixels 200 each have the sameoctagonal shape. In addition, the second pixels 200 are arrangeddiagonally and separated from each other by the first pixels 100. Thesecond pixels 200 emit blue light, and may include an organic emissionlayer for emitting blue light.

In a similar fashion, in the virtual square VS, each of the third pixels300 is separated from the first pixel 100 and the second pixels 200, andis centered at one of the second vertices P2 neighboring the firstvertices P1 of the virtual square VS. Each of the third pixels 300 has alarger area than the neighboring first pixel 100 and the same area aseach of the second pixels 200. Further, the third pixels have anoctagonal shape (e.g., similar to or the same as the second pixels 200).In FIG. 1, the third pixels 300 each have the same octagonal shape. Inaddition, the third pixels 300 are arranged diagonally and separatedfrom each other by the first pixels 100. The third pixels 300 emit redlight, and may include an organic emission layer for emitting red light.

The third pixels 300 and the second pixels 200 are spaced apart fromeach other and alternately arranged in rows, such as along a secondvirtual straight line VL2. In a similar fashion, the third pixels 300and the second pixels 200 are spaced apart from each other andalternately arranged in columns. Accordingly, in the virtual square VS,two of the second pixels 200 having their corresponding centerspositioned at the first vertices P1 and two of the third pixels 300having their corresponding centers positioned at the second vertices P2to enclose a corresponding one of the first pixels 100 (e.g., in thevirtual square VS).

As described above, the center of each of the second pixels 200 ispositioned at one of the first vertices P1 of the virtual square VS. Inaddition, the center of the corresponding first pixel 100 is the centerof the virtual square VS. Further, the center of each of the thirdpixels 300 is positioned at one of the second vertices P2. Moreover, thesecond pixels 200 and the third pixels 300 each have the same area.

As a non-limiting example, the distance (e.g., a shortest distance)between one of the first pixels 100 and an adjacent one of the secondpixels 200 is a first length L1, the distance between one of the firstpixels 100 and an adjacent one of the third pixels 300 is the same firstlength L1, and the distance between one of the second pixels 200 and anadjacent one of the third pixels 300 is the same first length L1, asshown in FIG. 1. In addition, the distance (e.g., a shortest distance)between the neighboring first pixels 100 is a second length L2 that islonger than the first length L1. It should be noted that L1, L2, L3, . .. may be used throughout to represent shortest distances betweencorresponding pixels.

Therefore, the gap of the first length L1 is formed between adjacentpairs of the first pixels 100 and the second pixels 200, betweenadjacent pairs of the first pixels 100 and the third pixels 300, andbetween adjacent pairs of the second pixels 200 and the third pixels300. In addition, the gap of the second length L2 that is longer thanthe first length L1 is formed between the neighboring ones of the firstpixels 100. This results in improved deposition reliability when using afine metal mask to form the green, blue, and red organic emission layersrespectively included in the first pixels 100, the second pixels 200,and the third pixels 300.

In addition, by enclosing each of the first pixels 100 by a pair of thesecond pixels 200 and a pair of the third pixels 300, the aperture ratioof the first pixels 100, the second pixels 200, and the third pixels 300may be improved. Accordingly, a manufacturing time and manufacturingcost of the entire OLED display may be reduced and the display qualityof the image of the OLED display may be improved.

As described above, in the pixel arrangement structure of the OLEDdisplay of FIG. 1, the first pixels 100, the second pixels 200, and thethird pixels 300 have polygonal shapes (e.g., the first pixels have aquadrilateral shape and the second pixels 200 and the third pixels 300have an octagonal shape). In addition, it is worth considering that thedeposition process of the organic emission layer is one of the uniquemanufacturing characteristics of the OLED display. Accordingly, toimprove the deposition reliability of the organic emission layer in thedeposition process using the fine metal mask and to improve the apertureratio of the first pixels 100, the second pixels 200, and the thirdpixels 300, the center of each of the first pixels 100 is positioned atthe center of a virtual square VS formed by a first pair of diagonalvertices P1 and a second pair of diagonal vertices P2. In the virtualsquare VS, the centers of a pair of the second pixels 200 are positionedat the first vertices P1, and the centers of a pair of the third pixels300 are positioned at the second vertices P2.

In addition, in the pixel arrangement structure of the OLED display ofFIG. 1, the first pixels 100, the second pixels 200, and the thirdpixels 300 respectively emit green, blue, and red light. However, inpixel arrangement structures of other OLED displays, the first pixels100, the second pixels 200, and the third pixels 300 may emit light ofdifferent colors. For example, at least one of the second pixels 200 orthe third pixels may emit white light.

Next, a pixel arrangement structure of an OLED display according to asecond exemplary embodiment will be described with reference to FIG. 2.Parts that are different from the exemplary embodiment of FIG. 1 will bedescribed, while the description of parts that are equivalent to thefirst exemplary embodiment may be omitted. For better comprehension andease of description, constituent elements of the second exemplaryembodiment that are the same as or similar to those of the firstembodiment of FIG. 1 will have the same reference numerals.

As shown in FIG. 2, the pixel arrangement structure of the OLED displayincludes a plurality of first pixels 100, a plurality of second pixels200, and a plurality of third pixels 300. The plurality of first pixels100 have the same quadrilateral shape (e.g., a parallelogram). Inaddition, the second pixels 200 have a larger area than the third pixels300. The second pixels 200 and the third pixels 300 may have polygonalshapes, such as octagonal or hexagonal (i.e., six-sided).

In a similar fashion to that of FIG. 1, the centers of a pair of thesecond pixels 200 are positioned at first vertices P1 along one diagonalof a virtual square VS having a center coinciding with a center of oneof the first pixels 100. In addition, the centers of a pair of the thirdpixels 300 are positioned at second vertices P2 along another diagonalof the virtual square VS. However, in FIG. 2, the second pixels 200 havea larger area than the third pixels 300.

As a non-limiting example, the distance between adjacent ones of thesecond pixels 200 and the third pixels 300 is a third length L3, whilethe distance between each of the first pixels 100 and adjacent ones ofthe second pixels 200 or the third pixels 300 have a same fourth lengthL4. In addition, the distance between neighboring ones of the firstpixels 100 is a fifth length L5 that is longer than the third length L3and the fourth length L4.

Accordingly, the gap of the fourth length L4 is formed between adjacentpairs of the first pixels 100 and the second pixels 200, and betweenadjacent pairs of the first pixels 100 and the third pixels 300. Inaddition, the gap of the third length L3 is formed between adjacentpairs of the second pixels 200 and the third pixels 300. Further, thegap of the fifth length L5 that is longer than the third length L3 andthe fourth length L4 is formed between the neighboring ones of the firstpixels 100. This results in improved deposition reliability in thedeposition process using the fine metal mask to form the green, blue,and red organic emission layers respectively included in the firstpixels 100, the second pixels 200, and the third pixels 300.

In addition, by enclosing each of the first pixels 100 by a pair of thesecond pixels 200 and a pair of the third pixels 300, the aperture ratioof the first pixels 100, the second pixels 200, and the third pixels 300may be improved. Accordingly, the manufacturing time and themanufacturing cost of the OLED display may be reduced and the displayquality of the image of the OLED display may be improved.

Further, in the pixel arrangement structure of the OLED display of FIG.2, the second pixels 200 that emit blue have the shortest life spanamong the first pixels 100, the second pixels 200, and the third pixels300. Accordingly, the second pixels 200 have a larger area than thethird pixels 300, thereby suppressing the deterioration of the life spanof the OLED display. That is, the pixel arrangement structure of theOLED display of FIG. 2 provides improved life span.

Next, a pixel arrangement structure of an OLED display according to athird exemplary embodiment will be described with reference to FIG. 3.Parts that are different from the above exemplary embodiments will bedescribed, while the description of parts that are equivalent to theabove exemplary embodiments may be omitted. For better comprehension andease of description, constituent elements of the third exemplaryembodiment that are the same as or similar to the above exemplaryembodiments will have the same reference numerals.

As shown in FIG. 3, the pixel arrangement structure of the OLED displayincludes a plurality of first pixels 100, a plurality of second pixels200, and a plurality of third pixels 300. Among the plurality of firstpixels 100, the neighboring first pixels 100 have a quadrilateral shape(e.g., parallelogram) and are symmetrical to each other. In addition,the second pixels 200 have a larger area than the third pixels 300. Thesecond pixels 200 and the third pixels may have polygonal shapes (e.g.,hexagonal or octagonal).

In a similar fashion to that of FIGS. 1-2, the centers of a pair of thesecond pixels 200 are positioned at first vertices P1 along one diagonalof a virtual square VS having a center coinciding with a center of oneof the first pixels 100. In addition, the centers of a pair of the thirdpixels 300 are positioned at second vertices P2 along another diagonalof the virtual square VS. However, in FIG. 3, the neighboring firstpixels 100 have a quadrilateral shape and are symmetrical to each other,while the second pixels 200 have a larger area than the third pixels300. This results in improved deposition reliability in the depositionprocess using the fine metal mask to form the green, blue, and redorganic emission layers respectively included in the first pixels 100,the second pixels 200, and the third pixels 300.

In addition, by placing each of the first pixels 100 between a pair ofthe second pixels 200 and between a pair of the third pixels 300, theaperture ratio of the first pixels 100, the second pixels 200, and thethird pixels 300 may be improved. Accordingly, the manufacturing timeand the manufacturing cost of the OLED display may be reduced and thedisplay quality of the image of the OLED display may be improved.

Further, in the pixel arrangement structure of the OLED display of FIG.3, the second pixels 200 that emit blue have the shortest life spanamong the first pixels 100, the second pixels 200, and the third pixels300. Accordingly, the second pixels 200 have a larger area than thethird pixels 300, thereby suppressing the deterioration of the life spanof the OLED display. That is, the pixel arrangement structure of theOLED display provides improved life span.

Next, a pixel arrangement structure of an OLED display according to afourth exemplary embodiment will be described with reference to FIG. 4.Parts that are different from the above exemplary embodiments will bedescribed, while the description of parts that are equivalent to theabove exemplary embodiments may be omitted. For better comprehension andease of description, constituent elements of the fourth exemplaryembodiment that are the same as or similar to the above exemplaryembodiments will have the same reference numerals.

As shown in FIG. 4, the pixel arrangement structure of the OLED displayincludes a plurality of first pixels 100, a plurality of second pixels200, and a plurality of third pixels 300. Among the plurality of firstpixels 100, the neighboring first pixels 100 have a quadrilateral shape(e.g., parallelogram) and are symmetrical to each other. In addition,the third pixels 300 have a larger area than the second pixels 200. Thesecond pixels 200 and the third pixels may have polygonal shapes (e.g.,hexagonal or octagonal).

In a similar fashion to that of FIGS. 1-3, the centers of a pair of thesecond pixels 200 are positioned at the first vertices P1 along onediagonal of a virtual square VS having a center coinciding with a centerof one of the first pixels 100. In addition, the centers of a pair ofthe third pixels 300 are positioned at second vertices P2 along anotherdiagonal of the virtual square VS. However, in FIG. 4, the neighboringfirst pixels 100 have a quadrilateral shape and are symmetrical to eachother, while the third pixels 300 have a larger area than the secondpixels 200. This results in improved deposition reliability in thedeposition process using the fine metal mask to form the green, blue,and red organic emission layers respectively included in the firstpixels 100, the second pixels 200, and the third pixels 300.

In addition, by enclosing each of the first pixels 100 by a pair of thesecond pixels 200 and a pair of the third pixels 300, the aperture ratioof the first pixels 100, the second pixels 200, and the third pixels 300may be improved. Accordingly, the manufacturing time and themanufacturing cost of the OLED display may be reduced and the displayquality of the image of the OLED display may be improved.

Next, a pixel arrangement structure of an OLED display according to afifth exemplary embodiment will be described with reference to FIG. 5.Parts that are different from the above exemplary embodiments will bedescribed, while the description of parts that are equivalent to theabove exemplary embodiments may be omitted. For better comprehension andease of description, constituent elements of the fifth exemplaryembodiment that are the same as or similar to the above exemplaryembodiments will have the same reference numerals.

As shown in FIG. 5, the pixel arrangement structure of the OLED displayincludes a plurality of first pixels 100, a plurality of second pixels200, and a plurality of third pixels 300. Among the plurality of firstpixels 100, the neighboring first pixels 100 have a octagonal shape andare symmetrical to each other. In addition, the second pixels 200 have alarger area than the third pixels 300. The second pixels 200 and thethird pixels 300 may have quadrilateral shapes (e.g., rhombus).

In a similar fashion to that of FIGS. 1-3, the centers of a pair of thesecond pixels 200 are positioned at the first vertices P1 along onediagonal of a virtual square VS having a center coinciding with a centerof one of the first pixels 100. In addition, the centers of a pair ofthe third pixels 300 are positioned at second vertices P2 along anotherdiagonal of the virtual square VS. However, in FIG. 5, the neighboringfirst pixels 100 have a octagonal shape and are symmetrical to eachother, while the second pixels 200 have a larger area than the thirdpixels 300. This results in improved deposition reliability in thedeposition process using the fine metal mask to form the green, blue,and red organic emission layers respectively included in the firstpixels 100, the second pixels 200, and the third pixels 300.

In addition, by enclosing each of the first pixels 100 by a pair of thesecond pixels 200 and a pair of the third pixels 300, the aperture ratioof the first pixels 100, the second pixels 200, and the third pixels 300may be improved. Accordingly, the manufacturing time and themanufacturing cost of the OLED display may be reduced and the displayquality of the image of the OLED display may be improved.

Hereinafter, a pixel arrangement structure (or pixel arrangement) of anOLED display according to an exemplary embodiment will be described withreference to FIG. 6. FIG. 6 is a view schematically showing a portion ofpixels forming an OLED display.

FIG. 6 shows a pixel arrangement structure of an OLED display accordingto an exemplary embodiment of the present invention.

As shown in FIG. 6, the pixel arrangement structure of the OLED displayincludes a plurality of first pixels 100, a plurality of second pixels200, and a plurality of third pixels 300.

According to one embodiment, the pixel refers to a minimum unit fordisplaying an image (for example, the minimum addressable unit of thedisplay).

In one embodiment, among the first pixels 100, the second pixels 200,and the third pixels 300, power lines for driving each of the pixels,such as a gate line, a data line, a driving power line, and the like,are located. In addition, in one embodiment, an insulation layer, suchas a pixel defining layer, for defining each of the pixels is disposed.Further, in one embodiment, an OLED including an anode, an organicemission layer, and a cathode to correspond to each of the first pixels100, the second pixels 200, and the third pixels 300 is disposed. Theseconfigurations are technologies known in the art and further descriptionthereof is omitted for ease of description. In one embodiment, the shapeof each of the pixels is defined by the power lines, the pixel defininglayer, the anode, or the like.

In the pixel arrangement of FIG. 6, each of the first pixels 100 has asmaller area (e.g., is smaller in area) than neighboring second pixels200 and third pixels 300, and has a polygon shape. In FIG. 6, the firstpixels 100 have an octagonal shape among the polygon shapes. In otherembodiments, the first pixels 100 have one or more of various polygonshapes such as a triangle, a rectangle, a pentagon, a hexagon, aheptagon, and the like. For example, the first pixels 100 that neighboreach other among the plurality of first pixels 100 have hexagon shapesthat are symmetrical to each other. In one embodiment, each of theplurality of first pixels 100 has the same hexagonal shape.

In one embodiment, the first pixels 100 are spaced apart from each otherand arranged in rows, such as along a first virtual straight line VL1.In one embodiment, the first pixels 100 emit green light, and include anorganic emission layer for emitting green light. In other embodiments,the first pixels 100 include an organic emission layer that emits lightof one or more of various colors such as blue, red, or white color foremitting blue light, red light, or white light.

In FIG. 6, the second pixels 200 are arranged diagonally with respect tothe first pixels 100, namely at first vertices P1 along one diagonal ofa virtual square VS having one of the first pixels 100 as a center point(or center) of the virtual square VS. In a similar fashion, in FIG. 6,the third pixels 300 are arranged diagonally with respect to the firstpixels 100, namely at second vertices P2 along the other diagonal of thevirtual square VS.

In the virtual square VS of FIG. 6, each of the second pixels 200 isseparated from the first pixel 100, and is centered at one of the firstvertices P1 of the virtual square VS. Each of the second pixels 200 hasa larger area than the neighboring first pixel 100 and the neighboringthird pixels 300, and has a hexagonal shape. In other embodiments, thesecond pixels 200 have one or more of various polygonal shapes such as atriangle, a rectangle, a pentagon, a hexagon, a heptagon, and the like.

In FIG. 6, the second pixels 200 each have the same hexagonal shape. Inaddition, the second pixels 200 are arranged diagonally and separatedfrom each other by the first pixels 100. In one embodiment, the secondpixels 200 emit blue light, and include an organic emission layer foremitting blue light. In other embodiments, the second pixels 200 includean organic emission layer that emits light of one or more of variouscolors such as red, green, or white for emitting red light, green light,or white light.

In a similar fashion, in the virtual square VS of FIG. 6, each of thethird pixels 300 is separated from the first pixel 100 and the secondpixels 200, and is centered at one of the second vertices P2 neighboringthe first vertices P1 of the virtual square VS. Each of the third pixels300 has a larger area than the neighboring first pixel 100 and a smallerarea than the neighboring second pixels 200. The third pixels 300 has aquadrilateral shape among polygon shapes. In other embodiments, thethird pixels 300 have one or more of various polygonal shapes such as atriangle, a rectangle, a pentagon, a hexagon, a heptagon, and the like.

In FIG. 6, the third pixels 300 each have the same quadrilateral shape.In addition, the third pixels 300 are arranged diagonally and separatedfrom each other by the first pixels 100. In one embodiment, the thirdpixels 300 emit red light, and include an organic emission layer foremitting red light. In other embodiments, the third pixels 300 includean organic emission layer that emits light of one or more of variouscolors such as blue, green, or white for emitting emit blue light, greenlight, or white light.

In FIG. 6, each of the second pixels 200 and the third pixels 300 has ahexagonal shape and a quadrilateral shape, respectively. In anotherembodiment, each of the second pixels 200 and the third pixels 300respectively has a quadrilateral shape and a hexagonal shape. That is,in this other embodiment, one of the second pixels 200 or the thirdpixels 300 has a hexagonal shape and the other has a quadrilateralshape.

In one embodiment, the first pixels 100, the second pixels 200, and thethird pixels 300 respectively emit green light, blue light, and redlight. In other embodiments, the first pixels 100, the second pixels200, and the third pixels 300 emit light of the same color. In stillother embodiments, the first pixels 100, the second pixels 200, and thethird pixels 300 emit light of different colors. In some embodiments,the first pixels 100 emit green light, and one of the second pixels 200or the third pixels 300 emit blue light while the other emit red light.

In FIG. 6, third pixels 300 and the second pixels 200 are spaced apartfrom each other and alternately arranged in rows, such as along a secondvirtual straight line VL2. In a similar fashion, in FIG. 6, the thirdpixels 300 and the second pixels 200 are spaced apart from each otherand alternately arranged in columns. Accordingly, in FIG. 6, in thevirtual square VS, two of the second pixels 200 have their correspondingcenters positioned at the first vertices P1 and two of the third pixels300 have their corresponding centers positioned at the second verticesP2 to enclose a corresponding one of the first pixels 100 in the virtualsquare VS.

As described and illustrated in FIG. 6, the center of each of the secondpixels 200 is positioned at one of the first vertices P1 of the virtualsquare VS. In addition, the center of the corresponding first pixel 100is the center of the virtual square VS. Further, the center of each ofthe third pixels 300 is positioned at one of the second vertices P2.Therefore, the plurality of second pixels 200 of which the centers arepositioned at the first vertices P1 and the plurality of third pixels300 of which the centers are positioned at the second vertices P2respectively enclose one of the first pixels 100 in the virtual squareVS.

Further, and as illustrated in FIG. 6, the first pixels 100, the secondpixels 200, and the third pixels 300 have polygon shapes. In FIG. 6, thedistance between one of the first pixels 100 and an adjacent one of thesecond pixels 200 as well as a distance between one of the first pixels100 and an adjacent one of the third pixels 300 is the same first lengthL1. In addition, a distance between one of the second pixels 200 and anadjacent one of the third pixels 300 is a second length L2 that isdifferent from the first length L1. Further, in FIG. 6, a distancebetween neighboring first pixels 100 is a third length L3 that is longerthan the first length L1 and the second length L2.

For example, in some embodiments, the first length L1 is between 15 um(micrometers) and 35 um, the second length L2 is between 20 um and 45um, and the third length L3 is between 25 um and 65 um.

Therefore, gaps of the first length L1 are formed between adjacent pairsof the first pixels 100 and the second pixels 200, and between adjacentpairs of the first pixels 100 and the third pixels 300. In addition, thegaps of the third length L3 that is longer than the first length L1 areformed between the neighboring ones of the first pixels 100. In oneembodiment, this results in improved deposition reliability in thedeposition process using the fine metal mask to form the green, blue,and red organic emission layers respectively included in the firstpixels 100, the second pixels 200, and the third pixels 300.

In addition, in one embodiment, the plurality of second pixels 200 andthe plurality of third pixels 300 are arranged to enclose the firstpixels 100 in the virtual squares VS so that an aperture ratio of eachof the first pixels 100, the second pixels 200, and the third pixels 300can be improved. Accordingly, in one embodiment, the manufacturing timeand the manufacturing cost of the OLED display is reduced and thedisplay quality of the image of the OLED display is improved.

Further, in the pixel arrangement structure of the OLED display of FIG.6 according to an exemplary embodiment of the present invention, thesecond pixels 200 that emit blue light have the shortest life span amongthe first pixels 100, the second pixels 200, and the third pixels 300.Accordingly, the second pixels 200 have a larger area than the firstpixels 100 and the third pixels 300, thereby suppressing thedeterioration of the life span of the OLED display. That is, in oneembodiment, the pixel arrangement structure of the OLED display of FIG.6 provides improved life span.

As described above, in the pixel arrangement structure of the OLEDdisplay of FIG. 6 according to an exemplary embodiment of the presentinvention, the first pixels 100, the second pixels 200, and the thirdpixels 300 have simple polygonal shapes such as an octagon, a hexagon,and a quadrangle. In consideration of the deposition process of theorganic emission layer, which in one embodiment is a uniquemanufacturing feature of the OLED display, a center of one of the firstpixels 100 is positioned at the center of the virtual square VS, acenter of one of the second pixels 200 is positioned at the first vertexP1, and a center of one of the third pixels 300 is positioned at thesecond vertex P2 to both improve deposition reliability of the organicemission layer in the deposition process using the fine metal mask andimprove an aperture of each of the first, second, and third pixels 100,200, and 300.

That is, according to an exemplary embodiment of the present inventionas illustrated in FIG. 6, the pixel arrangement structure of the OLEDdisplay includes a plurality of first pixels 100 having an octagonalshape, a plurality of second pixels 200 having a hexagonal shape, and aplurality of third pixels 300 having a quadrilateral shape. In one ormore embodiments, the shapes and arrangement of the first pixels 100,the second pixels 200, and the third pixels 300 improve the depositionreliability of the organic emission layer while also improving theaperture ratio of each of the first pixels 100, the second pixels, 200,and the third pixels 300.

While this invention has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments, but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims, and equivalents thereof.

DESCRIPTION OF SOME SYMBOLS

-   first pixel 100, second pixels 200, third pixels 300

What is claimed is:
 1. An organic light emitting diode (OLED) display,comprising: a plurality of individually addressable pixels fordisplaying an image, the individually addressable pixels being minimumaddressable units of the OLED display and comprising: a plurality of redpixels comprising an organic emission layer for emitting red light; aplurality of blue pixels comprising an organic emission layer foremitting blue light; and a plurality of green pixels comprising anorganic emission layer for emitting green light; wherein a first one ofthe red pixels has a center coinciding with a center of a virtualsquare, each vertex of the virtual square coinciding with a center of adifferent one of the red pixels; wherein the boundary of the virtualsquare only passes through eight of the plurality of pixels, of whichfour are blue pixels; wherein at least four green pixels are locatedentirely within the boundary of the virtual square; wherein theplurality of red pixels, the plurality of blue pixels, and the pluralityof green pixels are spaced apart from one another; wherein a shortestdistance between the first red pixel and one of the four green pixels isa first length that is smaller than a shortest distance between two ofthe four green pixels; wherein each of the four blue pixels throughwhich the boundary of the virtual square pass has a larger area thaneach of the four green pixels.
 2. The display of claim 1, wherein eachof the blue pixels through which the boundary of the virtual square passhas a larger area than that of the first red pixel.
 3. The display ofclaim 2, wherein the first red pixel has a larger area than each of thefour green pixels.
 4. The display of claim 2, wherein the first lengthis smaller than a shortest distance between one of the four blue pixelsand the first red pixel.
 5. The display of claim 4, wherein the one ofthe four green pixels has a different shape than the one of the fourblue pixels and the first red pixel.
 6. The display of claim 4, whereinthe one of the plurality of blue pixels has at least four sides.
 7. Thedisplay of claim 2, wherein the first length is equal to a shortestdistance between one of the four blue pixels and the first red pixel. 8.The display of claim 7, wherein the one of the four green pixels has adifferent shape than the one of the four blue pixels and the first redpixel.
 9. The display of claim 7, wherein the one of the plurality ofblue pixels has at least four sides.
 10. A method for manufacturing anorganic light emitting diode (OLED) display, comprising: depositing,using a fine metal mask, organic light-emitting material configured toemit a first color of light; forming a plurality of first pixels to emitthe first color of light; depositing, using a fine metal mask, organiclight-emitting material configured to emit a second color of light;forming a plurality of second pixels to emit the second color of light;depositing, using a fine metal mask, organic light-emitting materialconfigured to emit a third color of light; and forming a plurality ofthird pixels to emit the third color of light; wherein: the firstpixels, the second pixels, and the third pixels are individuallyaddressable pixels for displaying an image, the individually addressablepixels being minimum addressable units of the OLED display; one of thethird pixels has a center coinciding with a center of a virtual square,each vertex of the virtual square coinciding with a center of adifferent one of the third pixels; wherein the boundary of the virtualsquare only passes through eight of the individually addressable pixels,of which four are second pixels for emitting the second color of light;wherein at least four first pixels are located entirely within theboundary of the virtual square; wherein the plurality of third pixels,the plurality of second pixels, and the plurality of first pixels arespaced apart from one another; wherein a shortest distance between theone of the third pixels and one of the four first pixels is a firstlength that is smaller than a shortest distance between two of the fourfirst pixels; wherein each of the four second pixels through which theboundary of the virtual square pass has a larger area than each of thefour first pixels.
 11. The method of claim 10, wherein the one of thefour first pixels has a different shape than the one of the four secondpixels and the one of the third pixels.
 12. The method of claim 10,wherein the one of the plurality of second pixels has at least foursides.
 13. The method of claim 10, wherein the first pixels are formedbefore the second and third pixels are formed.
 14. The method of claim10, wherein the second pixels are formed before the first and thirdpixels are formed.
 15. The method of claim 10, wherein the third pixelsare formed before the first and second pixels are formed.
 16. The methodof claim 10, wherein the first pixels include an organic emission layerfor emitting green light, the second pixels include an organic emissionlayer for emitting blue light, and the third pixels include an organicemission layer for emitting red light.
 17. The method of claim 16,wherein each of the blue pixels through which the boundary of thevirtual square pass has a larger area than that of the first red pixel.18. The method of claim 17, wherein the one of the four first pixels hasa different shape than the one of the four second pixels and the one ofthe third pixels.
 19. The method of claim 17, wherein the one of theplurality of second pixels has at least four sides.
 20. The method ofclaim 17, wherein the one of the third pixels has a larger area thaneach of the four first pixels.
 21. The method of claim 20, wherein theone of the four first pixels has a different shape than the one of thefour second pixels and the one of the third pixels.
 22. The method ofclaim 20, wherein the one of the plurality of second pixels has at leastfour sides.
 23. The method of claim 16, wherein the first length issmaller than a shortest distance between one of the four second pixelsand the one of the third pixels.
 24. The method of claim 23, wherein theone of the four first pixels has a different shape than the one of thefour second pixels and the one of the third pixels.
 25. The method ofclaim 23, wherein the one of the plurality of second pixels has at leastfour sides.
 26. The method of claim 16, wherein the first length isequal to a shortest distance between one of the four second pixels andthe one of the third pixels.
 27. The method of claim 26, wherein the oneof the four first pixels has a different shape than the one of the foursecond pixels and the one of the third pixels.
 28. The method of claim26, wherein the one of the plurality of second pixels has at least foursides.